象山港沉积物与生物体中多氯联苯分布特征与暴露风险

Distribution features and exposure risk of polychlorinated biphenyls (PCBs) in sediments and marine organisms from Xiangshan Bay, China

为了研究邻近海域多氯联苯(PCBs)的残留水平与生态风险,2014年至2017年夏季在象山港11个监测站位采集沉积物与生物体样品,用气相色谱法测定10种指示性PCB单体的残留量,并对其分布特征以及食用暴露风险进行探讨与评价.结果表明,象山港海域表层沉积物中PCBs浓度在ND(未检出)至3.5 ng·g^-1之间,平均值为1.36 ng·g^-1.其中,低氯取代物在表层沉积物中检出率较高.沉积物空间分布格局显示,PCBs残留量集中在港中部.10种指示性PCB单体在9种生物样中均有检出,以五氯联苯和六氯联苯为主.PCBs在生物体内的残留量在ND至25.3 ng·g^-1之间.其中,锯缘青蟹体内的PCBs残留量较高(7.80 ng·g^-1).成人男性、成人女性与儿童的日均暴露量(ADD)分别为5.34、5.90、12.59 ng·kg^-1·d^-1,均低于美国EPA推荐的参考剂量(Reference Dose,RfD)和世界卫生组织(World Health Organization,WHO)设定的PCBs每日耐受量(Tolerable Daily Intake,TDI).健康风险评价结果显示,象山港内生物体对成人和儿童具有较低的非致癌健康风险,其致癌风险也在安全范围内.

Sediment and organism samples were collected during the summer of 2014—2017 at representative 11 sites in Xiangshan Bay,one of the most polluted waterways in China′s southeast coast.The concentration of 10 indicator PCB congeners were determined by gas chromatography for the purpose of evaluating the quality of the marine sediments and organism as well as the ecological risks of polychlorinated biphenyls(PCBs).The spatial Distribution of PCBs residue in marine sediment was also investigated.Result revealed that PCBs concentration in surface sediment ranged from ND(not detected)to 3.5 ng·g^-1(mean 1.36 ng·g^-1)with the highest residue in the central part of the Xiangshan Bay.Low chloride monomer category had the highest detection rate in sediments.PCBs residue in 9 types of marine organisms ranged from ND to 25.3 ng·g^-1.The highest concentration was observed in Scylla serrata(7.80 ng·g^-1).Ten indicative PCB were all detected in marine organisms dominated by Penta-CB and Hexa-CB.Average daily dose(ADD)for adults men,adults women and children were averaged at 5.34,5.90,12.59 ng·kg^-1·d^-1 respectively,all below the reference dose(RfD)and tolerable daily intake(TDI),indicating that non-carcinogenic risk and carcinogenic risk of marine organisms arised from the dietary exposure to PCBs was relatively small.